Medicines in heat

[clarabel82]

On some medicines it says on the box or in instructions "Do not store above 25 degrees C" or as I found on another box 30 degrees C. What happens if the medicines ARE kept above these temperatures? Only I work in a chemist where the ambient temperature is pushing 40 degrees C. Yes, we are all melting too!

[LazyGun]

I would imagine that the higher temperature is likely to cause a faster degredation of the active ingredient, thus shortening shelf life.

[Dizzieblonde]

The strength of them lessens - the active ingredients in some drugs are destroyed by changes in heat, some by exposure to light etc.

[AllYourBase]

Usually this is only a problem if it is stored continuously above these temperatures. For example, on a hot day a chemist shop does not have to throw away all it's drugs, because the vast majority of days are not hot. The shelf life will shorten, but not that makes any significant difference.
What you should worry about more is storing drugs in the fridge - if it says 4-8 degrees, then that's where it should be living all the time.